(1) Field of the Invention
The present invention relates generally to improved methods and apparatus for testing protective clothing such as gloves and other personal barriers used by health care providers and others who handle hazardous materials. More particularly, the present invention relates generally to methods and apparatus for testing medical gloves to identify defective holes or rips therein. Accordingly, the present invention is directed to novel and improved methods and devices of such character.
(2) Prior Art and General Background
One of the most critical current health concerns is the transmission of contagious diseases, such as the AIDS virus and the hepatitis B virus as well as other infectious diseases, through inadvertent direct contact. Such concerns have been heightened in the health provider population wherein health care professionals are routinely potentially exposed to such diseases during the performance of their duties and, in fact, have in some cases contracted such highly disabling and life threatening diseases through direct body contact. Usage of "rubber" examination and surgical gloves has represented the primary barrier to direct contact with the AIDS and hepatitis viruses. However, one of the drawbacks to the use of "rubber" gloves resides in the fact that the integrity of the glove is usually not evident on routine visual inspection. In particular, a number of studies have shown that a substantially large percentage of latex gloves, both surgical and examination, have pores of sufficient magnitude to allow for direct communication of potentially infectious agents through the gloves. In some studies, nearly thirty percent (30%) of all of the medical gloves tested were found to have impermissibly large openings.
Latex examination and surgical gloves are conventionally tested for quality pursuant to a number of testing standards developed by the American Society of Testing and Materials. For example, examination gloves are tested by filling the glove with approximately 300 milliliters of water at room temperature and observing the glove in a vertical position for a period of time, such as, typically, a minimum of two minutes. The emergence of water from the glove signals a failure of the glove. The minimum thickness for the typical rubber examination glove is 0.08 mm.
Latex surgical gloves, which are ordinarily employed in operating rooms, are tested by fastening the cuff of the glove to a circular mandrel. The glove is inflated with air pressure to a gage pressure of 1.5 kPa and the inflated glove is then immersed in water at room temperature to a depth of pf 200.+-. 10 mm above the tip of the middle finger. The immersion time is typically on the order of 1.5 minutes. The emergence of air bubbles from the glove is a signal of failure.
The adoption and implementation of glove testing standards has not resulted in the widespread proliferation of defect-free gloves for the medical professions. Additionally, a major deficiency of the above-discussed techniques for testing either rubber examination gloves or rubber surgical gloves is that the tests are time specific and neither account for or test for any subsequent emergence or formation of a defective hole or a tear in the glove. The presence of even statistically small numbers of defective gloves can result in very ominous consequences to the medical professions.
While the state of the art has been discussed above in the context of medical gloves, and the invention will be described below primarily in this context, it is to be understood that similar problems are presented by other medical apparel, such as surgical gowns, and by clothing used in the waste disposal field.